Question

What is the molal concentration of an aqueous calcium chloride solution that freezes at -2.43 degrees Celsius?

Answer 1

delta T = Kf*molality

solve for molality.

Answer 2

I Hate UT homework!!! Please help!! trapped in well!!!

Answer 3

[AI-generated answer — Explain Bot]

To determine the molal concentration of a solution, we need to know the freezing point depression constant (Kf) of the solvent and the change in freezing point (∆Tf) caused by the solute.

In this case, we are given that the solution freezes at -2.43 degrees Celsius, so the ∆Tf is -2.43 degrees Celsius. However, we need to convert this value to Kelvin since the freezing point depression equation requires temperatures in Kelvin.

To convert the temperature from Celsius to Kelvin, we add 273.15 to the given temperature. So, -2.43 degrees Celsius is equal to 270.72 Kelvin.

Now, we need to find the value of the freezing point depression constant (Kf) for the solvent. In this case, since it is an aqueous solution, we can assume the solvent is water. The freezing point depression constant for water is approximately 1.86 degrees Celsius/m (°C/m).

Finally, we can use the freezing point depression equation:

∆Tf = Kf * m

Where:
∆Tf is the change in freezing point in Kelvin,
Kf is the freezing point depression constant of the solvent, and
m is the molal concentration of the solute.

Rearranging the equation to solve for m:

m = ∆Tf / Kf

Substituting the values:

m = (-2.43 K) / (1.86 °C/m)

m ≈ -1.31 mol/kg

Therefore, the molal concentration of the aqueous calcium chloride solution is approximately -1.31 mol/kg.